Jin, Jeong-Un Hahn, Jae Ryang You, Nam-Ho 2024-01-19T11:33:30Z 2024-01-19T11:33:30Z 2022-08-04 2022-07 2470-1343 https://pubs.kist.re.kr/handle/201004/114887 In this study, polyimide (PI) with high carbonization yield was used as a precursor to prepare graphite films with high thermal conductivity. The crystallinity, grain size, and thermal conductivity of the graphite films were characterized and found to vary according to the chemical structure of the PI precursor. Aromatic PIs containing ortho-substituted hydroxyl groups in the PI main chain (DHB-BPDA) were synthesized by the polycondensation reaction of 3,3'-dihydroxybenzidine (DHB) and 3,3',4,4'- biphenyltetracarboxylic dianhydride (BPDA). The DHB-BPDA is converted to a polybenzoxazole (PBO) structure through thermolysis reaction during carbonization. The PBO containing a benzene ring and a heterocycle group can provide a strong main chain and high thermal stability due to its resonant structure. The graphite film prepared from DHB-BPDA exhibited a large grain size (63.727 nm) and a high thermal conductivity of 916 W/(mK). English ACS Publications Structural Effect of Polyimide Precursors on Highly Thermally Conductive Graphite Films Article 10.1021/acsomega.2c02731 1 ACS OMEGA, v.7, no.29, pp.25565 - 25572 ACS OMEGA 7 29 25565 25572 Y scie scopus 000828933400001 2-s2.0-85135240259 Chemistry, Multidisciplinary Chemistry Article POLYBENZOXAZOLE NANOFIBERS TEXTURAL CHANGES CARBON-FILM GRAPHITIZATION CARBONIZATION KAPTON CONVERSION HEAT